Hydrogen production from sugarcane vinasse in anaerobic fluidized bed reactor under thermophilic conditions

Abstract

Currently, 80% of world energy is generated by fossil fuels. However, we know that the reserves of these fuels are scarce and its compounds generate many environmental problems. Thus, in the 1990s, the interest in the study of renewable fuels and less harmful to the environment. Hydrogen is an alternative to replace fossil fuels that generate carbon dioxide as a product of burning, potentiating the greenhouse effect. The H2 is considered a clean fuel, produces water as a product in cells and has a high energy conversion of energy per unit mass. Several works have been developed in order to obtain biologically H2 as an alternative to using fossil fuels for power generation. This production can occur via two biological processes: photosynthesis and fermentation process, and the anaerobic fermentation is technically simpler and hydrogen can be obtained from organic matter present in wastewaters. This organic matter is a cheap raw material to integrate anaerobic digestion, and can be used to produce compounds of value as volatile fatty acids (VFA - or organic acids) and alcohols, and generate energy as methane and hydrogen. Therefore, the objective of this study is to evaluate the hydrogen production in anaerobic fluidized bed reactor (AFBR) treating vinasse under thermophilic conditions (55 ºC). Different values of COD in the influent vinasse (5,000 to 40,000 mg / L) and different hydraulic retention times (HRT) (14-4 h) will be used in order to define the best operating conditions of the system in order to achieve greater efficiency in production H2. (AU)